Starting device for sliding doors



1964 J. E. SPARGUR ETAL 3,157,224

STARTING DEVICE FOR SLIDING DOORS Filed Feb. 5, 1962 2 Sheets-Sheet 1INVENTORS JosEPH E. Somzeua g n-500022 E.

53 I"! BY Q TSZ ATTORNEYS 1954 I J. E. SPARGUR ETAL 3,

STARTING DEVICE FOR SLIDING DOORS Filed Feb. 5,- 1962 I 2 Sheets-Sheet 2TNVENTORS q JOSEPH -E. Swazeuz 4\ IS imeoooraec. Muzz.

ATTORNEYS United States Patent 3 157,224 STARTING DEVIUE FUR SLIDWGDUGFS .Ioseph E. Eipargur, 517 7th Ave. N., and Theodore t3. Mnrr, 2001Wentworth Ave, both of South St. Paul, Minn.

Filed Feb. 1%2, Ser. No. 171,1Q0 3 Claims. Ji. lob-189) This inventionrelates to starting devices for sliding doors, and more particularly toa starting device capable of easily initiating the opening of anoverhead garage door.

Our invention is the outgrowth of extensive experience in theinstallation and service of roll-up or overhead garage doors. It wasfound that the major complaint leading to numerous service calls was thedifiiculty for the average person in getting enough thrust into theinitial lift to start the door moving in its normal upward movement.

The principal reason for this starting difficulty lies in the fact thatthe door must be designed so that it moves easily from partial to fullopening but is tight against the door stop when it is fully closed. Thistightness is especially necessary in severe climates. The result hasbeen that the door is designed for a wedging or carnming action as itmoves into completely closed position. This is achieved by the form,angle and location of the guide track or by interlocking cam and wedgemembers, particularly in the case of doors that swing into overheadposition about a pivot. The heavy door when closed tends to tighten thewedging action, and the result is a binding requiring a considerableforce to break.

A secondary reason for the binding of the door is the action of waterand wet snow which tend to work around the edges of the door, and whenfrozen act as an adhesive, this bond requiring a great deal of force tobreak.

It is an object of the invention, therefore, to provide a startingdevice which enables any person, with the application of a moderateamount of force, to start the operation of a garage door of the overheadtype and move it sufiiciently far from the closed position that anyforces binding the door against normal action are broken.

A further object of the invention is to provide a starting device whichutilizes the power of the leg muscles and the weight of the personoperating the door starter, giving maximum effect with minimum effort.

Still another object of the invention is to provide a starting devicewhich enables the operator to continue to apply power evenly as the doormoves a substantial distance to open position, insuring a completebreaking of the binding forces.

Still another object of the invention is to provide a starting devicewhich may be operated from the inside or outside of the garage door, andwhich may be easily installed by the boring of one hole through the edgeof the bottom panel and the setting of a minimum number of screws.

Another object of the invention is to provide a starting device whichgives a maximum starting force applied slowly when the device is in thefirst stages of its cycle, and then by means of a novel shiftingfulcrum, changes to a reduced force operating at increased speed througha greater distance, whereby the door is given a strong impetus towardthe full open position after the initial binding forces have beenbroken.

Still another object of the invention is to provide a starting devicehaving means for withdrawing the device to retracted position withoutdamage to the device or injury to the operator.

Finally, it is an object of the invention to provide a starting devicewhich is applicable to any type of overhead garage door and to manyother types of closures, if desired, with low first cost, a minimumnumber of parts and without the installation of a wear plate, theshifting fulcrum point avoiding any concentration of force on theconcrete garage floor or runway.

With the above and other objects in mind, as will be presently apparent,the invention consists in general of certain novel combinations of partshereinafter fully described, illustrated in the accompanying drawings,and particularly claimed.

In the drawings, like characters of reference indicate like parts in theseveral views, and

FIGURE 1 is a fragmentary, isometric view, showing the device as appliedto a typical overhead garage door installation, the door being closedand the starting device being ready for use;

FIGURE 2 is a fragmentary rear elevational view of a door, showing theinvention in full line in retracted position and in dotted line in fullydepressed position at the end of the starting stroke;

FIGURE 3 is a top view of the invention mounted on a door and showingthe inner and outer operating arms, the view being taken along the line3-3 of FIGURE 2;

FIGURE 4 is a vertical section taken along the line 4-4 of FIGURE 2;

FIGURE 5 is a fragmentary vertical section taken on the line 5-5 ofFIGURE 4;

FIGURE 6 is a fragmentary vertical section taken on the line 6--6 ofFIG. 4 to show the fastening member at the ends of the shaft;

FIGURE 7 is an exploded isometric view of the starter assembly;

FIGURE 8 is a modification of the basic invention employing two startermembers for heavy duty use; and

FIGURE 9 is a fragmentary vertical section taken on the line 99 ofFIGURE 8.

In the drawings, the letter D identifies a garage door to which theinvention is applied. The details of the overhead garage door, asillustrated, are not a part of the invention, and the invention may beapplied to any one of several types of overhead doors. In the foldingpanel type shown, the invention is applied to the lower panel LP, asshown in FIGURE 1.

The device is applied to the panel LP by drilling a single transversehole 16 spaced from the lower edge of the panel. Through the hole lit)is placed a squared shaft 11, rotatable in the said hole. The shaft isshown as squared throughout its length, but it will be seen that theshaft could be round at its mid portion for better bearing relation witha pair of supporting plates 12 and 13, the ends being squared. Theplates 12 and 13 are securely fastened to opposite faces of the panel LPby screws 14. These plates preferably extend to the lower edge of panelLP.

On the inner end of the shaft 11 is mounted the main operating arm 15.This arm has a squared aperture 16 at its inner end to key the arm andshaft for joint rotation, the aperture extending through a boss portion17 which defines a bearing face 18 which engages the plate 13.

The arm 15 is generally curved, the lower carnming face 19 serving animportantfunction as a shifting fulcrum during the starting operation.At its lower end 20, the curved face 19 has exactly the same radialdistance from the longitudinal axis of rotation of the shaft 11 as doesthe lower edge of the door panel. This is a relatively short radius, andthe radius of curvature relative to the pivotal axis on shaft 11constantly increases with longer radii. When the door is closed, and thestarting device fully retracted, the lower end 20 of face 19 is incontact with the floor F of the building. Thus, the face 19 does notrepresent the true are of a circle but the curvature thereof is such asto permit the development of maximum force as the door D first raises,and the shifting of the fulcrum of the arm so as to change theforce-distancespeed ratio. The outer end 21 of the face 19 flattens outto permit proper orientation of the foot pressure pedal 2 Spaced fromthe boss portion 17 by a relatively short distance is the projection 23,which is drilled to pivotally receive the lower end of a piston shaft24. The piston shaft has at its outer end a piston 25 which reciprocatesin a cylinder 26. Between the piston 25 and the lower end of thecylinder 27 is a relatively long compression spring 28. The upper end 29of the cylinder 26 is provided with a bleed port or orifice (not shown)adjusted by means of the screw 30. A small bracket member 31 ispivotally attached to the panel LP. The spring 28 returns the arm 15 atthe end of its operating stroke, but the piston and bleed orificecontrol the rate of return. A bolt 32 secured the piston shaft 24 to theprojection 23.

The arm 15 is held against its supporting plate 13 by means of aremovable fastening device 33 held in an annular groove 34 in the shaft11.

At the opposite end of the shaft 11 and on the outside of the door is asecond operating arm 35. This arm has a squared aperture 36, cooperativewith the squared shaft 11, which extends through a bearing boss portion37. The inner face of this boss portion bears against the sup portingplate 12. A fastening member 33a fastens the arm 35 on the shaft 11 inthe same manner as the arm 15 is fastened. The arm in this case isstraight and is pro vided with a pressure pedal 38.

In FIGURES 8 and 9 there is shown a modification of the structureparticularly useful for heavy duty installations. In this form the basicassembly of the principal form is paired, with two arms 15 being used,as shown, one being the reverse of the other. The only change in the arm15 is that the pressure pedal 22 is omitted, and apertures are bored inthe ends to freely receive the pivot bolts 39. These bolts are slidablyand pivotally mounted in an elongated slot 40 in a bracket 41. Thebracket 41 is preferably L-shaped in cross-section, as shown in FIG- URE9, providing a forwardly extending flange 42. To this flange is attachedthe piston shaft 24 of the cylinder 26, and one spring and check unitserves as a return for both arms 15. The upper face of the flange 42serves as a foot plate. In FIGURES 8 and 9, the modification is shown asan interior starting device only, but outer arms may be applied, with abracket member similar to the bracket 41 connecting the ends of the twoarms.

Operation The operation of the device is shown by the dotted linepositions of elements in FIGURE 2. The starter is normally held by thespring 28 in the fully retracted, full line position. The operatorplaces his foot on the pedal 22, applying an easy, steady force. Thelower end of the face 19 fulcrums on the floor F, forcing the doorupwardly. As the door D moves upwardly, the pivot shaft 11 movesupwardly in a straight line and the fulcrum point shifts to the right,until the device and the door reach the dotted line position as shown inFIGURE 2. This structure provides maximum power at the start whenresistance is greatest, the length of the lever arm being great relativeto the force arm. As the door begins to open, the shifting fulcrumchanges the relative lengths of the lever arm and the force arm,decreasing the effective power in the force arm but increasing its speedand distance of travel relative to the lever arm. This is desirable inthat the first part of the starting stroke is directed to maximum powerwithout distance, and at a slow speed, while the remainder of thestarting stroke is 4 directed toward giving the door a faster impetus inthe upward direction when the wedging and binding forces have beenbroken. This final movement is then aided by the counterbalance springsand hand force applied to the door by the operator.

This compound action of the starting device is an important part of theinvention and helps to make it a highly practical device. It will beseen that the starting device may be operated from inside or outside ofthe door. The return stroke is positive and strong but is checked by theaction of the piston 25 and bleed orifice to prevent injury or damage.The shifting fulcrum has the added advantage of avoiding concentratedwear on the garage floor and a wear plate is unnecessary.

The operation of the modification of FIGURES 8 and 9 is similar to thatof the basic form. Foot pressure is applied to the flange 42 and thedoor is moved upwardly. As the arms 15 pivot to the dotted line positionof FIG- URE 8, the bolts 39 slide in the slot 40 to permit the bracket41 to move downwardly against the force of the spring 28. The pair oflevers gives greater starting force and generally more symmetricaldistribution and balance of the forces, permitting greater initial forceto be applied by the operator without damage to the components of thestarting device.

While there has been herein shown and described the preferredembodiments of the invention, it is nevertheless to be understood thatminor changes may be made therein without departing from the spirit andscope of the invention as claimed.

What is claimed is:

l. A starting device in combination with a vertically moveable garagedoor, including an operating arm, means mounting said operating arm onsaid door adjacent the lower end thereof, which end when said door isclosed moves into engagement with a floor surface forming one edge of adoor opening for said vertically movable door, said mounting meanspivotally connecting said arm at its inner end to said door about apivot axis which is substantially normal to the plane of said door andwhich is closely adjacent the end wall of the lower end of said door,said arm having adjacent its opposite outer end an upwardly directedfoot pedal surface for downward foot pressure in a plane substantiallyparallel to the plane of said door, said arm further having on its loweredge between said pivot means and said foot pedal a floor engagingfulcrum surface, and resilient means biasing said arm and said fulcrumsurface into a retracted position, whereby said fulcrum surface isnormally out of engagement with said floor surface but may be moved intoengagement therewith by the applied weight of a person operating saidstarting device, said fulcrum surface being in the form of an elongated,curved camming face directed toward and engageable with said floorsurface when said door is closed, said camming face extending along saidarm and having a relatively short radius adjacent said pivot means and aconstantly increasing radius relative to said pivot means toward theouter end, whereby said door will be started slowly with maximum forceand then will be moved more quickly but with lesser force a substantialdistance toward open position.

2. A structure as set forth in claim 1, wherein said mounting meansincludes a shaft extending through said door, said operating arm beingfixed to one end of said shaft, and a second operating arm on the otherside of said door attached to the other end of said shaft.

3. A starting device in combination with a vertically sliding door,including a pair of operating arms mounted on said door closely adjacentthe free leading edge thereof, which edge when said door is closedslides into engagement with a surface forming one edge of a door openingfor said sliding door, said arms each being pivotally mounted on saiddoor about a pivot axis normal to the plane of said door and havingtheir free ends inwardly directed one toward the other, each of saidarms having an elongated curved camming face directed toward and incontact with said surface when said door is closed, said camrning faceseach having a relatively short radius at an inner terminal end adjacentits pivotal axis and a constantly increasing radius relative to itspivotal axis toward its outer end, an elongated foot pressure memberconnecting said free ends of said arms, said member having alongitudinal elongated slot therein, said free ends having pivotelements freely slidable in said slot, and means connected to said footpressure member for retracting said arms to retracted position from anextended operating position.

References Cited by the Examiner UNITED STATES PATENTS 6/16 Elvin 268316/34 Henderson 2019 1/39 Friend 268 31 8/ 46 Hofiman 26872 3/53 Denkeret al 268-72 FOREIGN PATENTS 7/ 39 Australia.

HARRISON R. MOSELEY, Primary Examiner.

NORTON ANSI-1BR, Examiner.

1. A STARTING DEVICE IN COMBINATION WITH A VERTICALLY MOVEABLE GARAGEDOOR, INCLUDING AN OPERATING ARM, MEANS MOUNTING SAID OPERATING ARM ONSAID DOOR ADJACENT THE LOWER END THEREOF, WHICH END WHEN SAID DOOR ISCLOSED MOVES INTO ENGAGEMENT WITH A FLOOR SURFACE FORMING ONE EDGE OF ADOOR OPENING FOR SAID VERTICALLY MOVABLE DOOR, SAID MOUNTING MEANSPIVOTALLY CONNECTING SAID ARM AT ITS INNER END TO SAID DOOR ABOUT APIVOT AXIS WHICH IS SUBSTANTIALLY NORMAL TO THE PLANE OF SAID DOOR ANDWHICH IS CLOSELY ADJACENT THE END WALL OF THE LOWER END OF SAID DOOR,SAID ARM HAVING ADJACENT ITS OPPOSITE OUTER END AN UPWARDLY DIRECTEDFOOT PEDAL SURFACE FOR DOWNWARD FOOT PRESSURE IN A PLANE SUBSTANTIALLYPARALLEL TO THE PLANE OF SAID DOOR, SAID ARM FURTHER HAVING ON ITS LOWEREDGE BETWEEN SAID PIVOT MEANS AND SAID FOOT PEDAL A FLOOR ENGAGINGFULCRUM SURFACE, AND RESILIENT MEANS BIASING SAID ARM AND SAID FULCRUMSURFACE INTO A RETRACTED POSITION, WHEREBY SAID FULCRUM SURFACE ISNORMALLY OUT OF ENGAGEMENT WITH SAID FLOOR SURFACE BUT MAY BE MOVED INTOENGAGEMENT THEREWITH BY THE APPLIED WEIGHT OF A PERSON OPERATING SAIDSTARTING DEVICE, SAID FULCRUM SURFACE BEING IN THE FORM OF AN ELONGATED,CURVED CAMMING FACE DIRECTED TOWARD AND ENGAGEABLE WITH SAID FLOORSURFACE WHEN SAID DOOR IS CLOSED, SAID CAMMING FACE EXTENDING ALONG SAIDARM AND HAVING A RELATIVELY SHORT RADIUS ADJACENT SAID PIVOT MEANS AND ACONSTANTLY INCREASING RADIUS RELATIVE TO SAID PIVOT MEANS TOWARD THEOUTER END, WHEREBY SAID DOOR WILL BE STARTED SLOWLY WITH MAXIMUM FORCEAND THEN WILL BE MOVED MORE QUICKLY BUT WITH LESSER FORCE A SUBSTANTIALDISTANCE TOWARD OPEN POSITION.